Test plates for chemical or biochemical analysis which contain a plurality of individual wells or reaction chambers are well known laboratory tools. Such devices have been employed for a broad variety of purposes and assays, and are exemplified in U.S. Pat. Nos. 4,734,192 and 5,009,780, for example. Microporous membrane filters and filtration devices containing the same have become especially useful with many of the recently developed cell culture techniques, assays, and sample preparation methods, especially in the fields of virology, immunology, genetics, drug discovery, etc. Typically, a 96-well filtration plate is used to conduct multiple sample preparations or assays simultaneously. One such filtration device commercially available from Millipore Corporation under the name “Multiscreen” is a 96-well filter plate that can be loaded with adsorptive filter materials or particles. However, with the thousands of samples that can be analyzed in a single day for genotyping, for example, even a, 96-well plate, which allows the simultaneous treatment of 96 samples, can be inadequate.
In addition, flexibility in the dimensions of multi-well plates is desirable in view of the wide variety of applications that can be performed. Membrane type, well geometry and layout are important criteria in choosing the appropriate sample preparation device for a particular operation. Furthermore, many modern analytical techniques such as matrix assisted laser desorption ionization, time of flight, mass spectrometry (MALDI TOF MS) and 96X capillary electrophoresis systems require only a small amount of sample for analysis. Traditional 96-well devices often contain far more volume than is required for these high performance analytical instruments.
It would therefore be desirable to provide a multi-well plate that allows for the simultaneous treatment of hundreds or thousands of samples. It also would be desirable to provide a multi-well sample preparation array that is easily manufacturable and reproducible, thereby providing flexibility in design to accommodate a particular application.
It also would be desirable to produce a sample preparation array that can process smaller sample volumes.
It also would be desirable to produce a sample preparation array suitable for direct analysis by MALDI TOF mass spectrometry.